Pollution of the urban environment is fast becoming a grave threat to urban dwellers as levels of toxicity increase to beyond safe limits. There are many kinds of air pollutants, and the most common and measured air pollutants are: carbon dioxide (CO2), carbon monoxide (CO), sulfur dioxide (SO2), nitric oxide (NO), nitrogen dioxide (NO2), nitrous oxide (N2O), suspended particles (PM 10 or PM 2.5), ozone (O3), and the like.
There are well known options in the art for collecting environmental pollution data by means of air pollution detection devices, such as sensors. Pollution sensors may be located in static locations, or allowed to roam on an entity. For example, a plurality of air pollution detecting devices may be selectively installed in vehicles, motorbikes, bicycles, or users' portable paraphernalia, such as a helmet worn by a motorbike rider. Air pollution information of various geographic locations over a vast area is obtainable while the vehicles or the users keep moving around.
Global Positioning System (GPS) based navigation systems are known that use stored maps to do route planning based on distance, speed limits and user preference of types of roads. Such systems are capable of providing routes based upon the starting point and end destination of a user. The resulting route chosen is adequate, but not necessarily least polluted.